It is unknown whether the flavonoid rutin can protect the silver catfish liver in response to exposure to a known stressor, such as the prophylactic usage of the antimicrobial agent oxytetracycline. ...Thus, the current study aimed to assess the effect of rutin incorporation into the silver catfish diet formulation on oxytetracycline-induced liver oxidative stress and apoptosis. Fish were split into four groups as follows: control, rutin (1.5 g kg diet−1), oxytetracycline (0.1 g kg diet−1) and rutin+oxytetracycline (1.5 g kg diet−1 and 0.1 g kg diet−1, respectively). After two weeks of feeding with the different diets (standard, rutin-, oxytetracycline and rutin+oxytetracycline-added diets), fish were euthanized to collect the liver. Although the rutin-added diet was unable to recover glutathione peroxidase activity, ascorbic acid and reduced glutathione (GSH) levels, which were depleted due to oxytetracycline consumption, it markedly diminished the oxidized glutathione (GSSG) content, thus decreasing the GSSG to GSH ratio, an important index of oxidative stress. It also increased glutathione reductase and markedly augmented glucose-6-phosphate dehydrogenase activities, which were declined after oxytetracycline ingestion. Furthermore, the rutin-added diet reestablished superoxide dismutase and catalase activities and reduced lipid peroxidation, nitric oxide and superoxide anion levels as well, all changes resulting from oxytetracycline consumption. Finally, it also prevented oxytetracycline-induced apoptosis through increasing heat shock protein 70 and markedly decreasing high mobility group box 1 and, consequently, reducing cleaved caspase-3 protein levels. Therefore, in conclusion, the incorporation of this flavonoid to the silver catfish diet protected the liver against oxytetracycline-induced liver oxidative stress and apoptosis.
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•Rutin diminished lipid peroxidation in liver of oxytetracycline-fed fish.•Rutin decreased oxidized to reduced glutathione ratio in oxytetracycline-fed fish.•Rutin increased glucose-6-phosphate dehydrogenase in oxytetracycline-fed fish.•Rutin reduced oxytetracycline-induced apoptosis decreasing cleaved caspase-3.
We analysed the effects of quercetin-containing diet on blood parameters, antioxidant status and pituitary hormone expression in silver catfish. Diets containing three concentrations of quercetin (0, ...0.15 and 0.30%) were provided to fish once a day. The results indicated that quercetin did not promote any significant change on the haematological and biochemical parameters measured. Fish that received the diet with quercetin presented decreased lipid peroxidation (LPO) (measured by lipid hydroperoxides and thiobarbituric acid reactive substances) in all tissues evaluated. On the other hand, the activity of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase were higher in tissues of fish fed with diets containing quercetin. Additionally, the content of non-protein thiols, total reactive antioxidant potential and ascorbic acid were also higher in tissues of quercetin fed fish. Finally, there was no changes regarding cortisol levels and the expression of growth hormone, prolactin and somatolactin in fish fed with quercetin when compared with the control. Our results suggests that supplementation of silver catfish diet with quercetin is beneficial since it reduced the LPO and increased antioxidant capacity in vital tissues of fish without having any impact on haematological and biochemical parameters, and on pituitary hormone gene expression.
We propose quercetin as supplement in fish diets.
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•Diets containing quercetin did not influence the blood parameters.•Diets containing quercetin decreased the lipoperoxidation in tissues of silver catfish.•Diets containing quercetin improved the antioxidant system defence in tissues of fish.•Diets containing quercetin did not influence the expression of pituitary hormones.
Protective or ameliorative effects of quercetin on the oxytetracycline (OTC) induced oxidative stress and presence of OTC residues in the muscle of silver catfish (Rhamdia quelen) were assessed. Fish ...were divided into four different experimental groups and received the following experimental diets for 14 or 21days: (i)-control; (ii)-quercetin; (iii)-OTC; or (iv)-quercetin plus OTC. Muscle samples were collected at the end of the experiment and analyzed for the oxidant/antioxidant status and presence of OTC residues. The OTC values in muscle of fish were lower than the quantification limit. There was a significant increase on lipid peroxidation and protein carbonyl content in the muscle of OTC-treated fish at 14 and 21days. Treatment with quercetin avoided this increase in the groups that received diet with quercetin plus OTC. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities decreased in the muscle of OTC-treated fish at 14days. Quercetin was able to avoid the decrease of GPx activity in the group that fed diet with quercetin plus OTC. After 21days of treatment there was a decrease of SOD, GPx and glutathione S-transferase activities in the muscle of OTC-treated fish. Quercetin was able prevent the decrease of SOD activity in the group that received diet with quercetin plus OTC. The glutathione reductase activity was higher in quercetin group at 14 and 21days of treatment. Ascorbic acid (AA) content increased in quercetin and quercetin plus OTC groups after 14days of treatment. After 21days of treatment, the AA and non-protein thiols content decreased in the muscle of OTC-treated fish. Thus, the present study demonstrates that quercetin protects the muscle from the OTC-induced oxidative stress, suggesting that it may be a useful compound to minimize the adverse effects in fish requiring treatment with OTC.
•Oxytetracycline led to oxidative stress in the muscle of fish in the different time of administration.•Quercetin demonstrated to be able to protect the tissue from oxidative stress caused by oxytetracycline in different time of administration.•Values of oxytetracycline residues in the muscle were lower than the limit of quantification.
To investigate the effects of rapid anesthesia and long-term sedation with the essential oils (EOs) of Myrcia sylvatica (EOMS) and Curcuma longa (EOCL) on biochemical and oxidative parameters in ...matrinxã.
Prospective, randomized, laboratory experiment.
A total of 72 matrinxã (Brycon amazonicus) adults weighing 404.8 ± 27.9 g were divided into eight groups of nine fish.
Biochemical and oxidative effects were investigated in plasma and tissues of matrinxã subjected to rapid anesthesia (5 minutes) or long-term sedation (360 minutes, simulating the practice of transport) with EOMS (200 μL L
and 10 μL L
, respectively) and EOCL (500 μL L
and 40 μL L
, respectively).
Transport simulation without sedation or anesthesia increased lipid peroxidation levels in the gills and kidney of fish in the control group. Anesthesia and sedation with EOs decreased cortisol concentrations and increased lactate concentrations compared with controls. Lipid peroxidation was lower in the brain, gills, liver and kidney of sedated and anesthetized fish, than in the control group. Anesthesia with EOs increased the activity of superoxide dismutase and glutathione-S-transferase in the brain, and catalase in the liver and gills, compared with controls. Long-term sedation with EOs increased superoxide dismutase, glutathione peroxidase and glutathione reductase activities in the brain, catalase in the liver, glutathione peroxidase and glutathione reductase in the gills and superoxide dismutase in the kidney. In general, nonprotein thiols content and total reactive antioxidant potential of tissues were higher after anesthesia and sedation with EOs compared with the control group.
The concentrations of EOMS and EOCL used were effective at preventing a stress response and excess of reactive oxygen species formation. For these reasons, these substances may be recommended for use in the transportation of fish to improve survival and animal welfare.
It is still debated if pre-existing minority drug-resistant HIV-1 variants (MVs) affect the virological outcomes of first-line NNRTI-containing ART.
This Europe-wide case-control study included ...ART-naive subjects infected with drug-susceptible HIV-1 as revealed by population sequencing, who achieved virological suppression on first-line ART including one NNRTI. Cases experienced virological failure and controls were subjects from the same cohort whose viraemia remained suppressed at a matched time since initiation of ART. Blinded, centralized 454 pyrosequencing with parallel bioinformatic analysis in two laboratories was used to identify MVs in the 1%-25% frequency range. ORs of virological failure according to MV detection were estimated by logistic regression.
Two hundred and sixty samples (76 cases and 184 controls), mostly subtype B (73.5%), were used for the analysis. Identical MVs were detected in the two laboratories. 31.6% of cases and 16.8% of controls harboured pre-existing MVs. Detection of at least one MV versus no MVs was associated with an increased risk of virological failure (OR = 2.75, 95% CI = 1.35-5.60, P = 0.005); similar associations were observed for at least one MV versus no NRTI MVs (OR = 2.27, 95% CI = 0.76-6.77, P = 0.140) and at least one MV versus no NNRTI MVs (OR = 2.41, 95% CI = 1.12-5.18, P = 0.024). A dose-effect relationship between virological failure and mutational load was found.
Pre-existing MVs more than double the risk of virological failure to first-line NNRTI-based ART.
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